can there be a way to use microwaves or radiowaves to make electricity?

Answer 1

yes, radio "waves" and light "waves" are all actually photons.

for light, we use a solar panel, for radio frequencies, a device called a RECTENNA, combines an antenna with a diode to convert these photons to electrical energy.

there have been proposals to put giant satellite solar power stations in space, then beam the energy to earth as microwaves, to be converted to electricity by fields of rectenna arrays.

Answer 2

The earliest work in the area of wireless transmission via radio waves was performed by Heinrich Rudolf Hertz in 1888. A few years later Guglielmo Marconi worked with a modified form of Hertz's transmitter. Nikola Tesla also investigated radio transmission and reception using a greatly improved transmitter.

Japanese researcher Hidetsugu Yagi also investigated wireless energy transmission using a directional array antenna that he designed. In February 1926, Yagi and Uda published their first paper on the tuned high gain directional array now known as the Yagi antenna. While it did not prove to be particularly useful for power transmission, this beam antenna has been widely adopted throughout the broadcasting and wireless telecommunications industries due to its exceptional performance characteristics and robustness.

Power transmission via radio waves is achieved by using shorter wavelengths of electromagnetic radiation, typically in the microwave range. A rectenna may be used to convert the microwave energy back into electricity. Conversion efficiencies exceeding 95% have been realized in this manner. Power beaming using microwaves has been proposed for the transmission of energy from orbiting solar power satellites to earth and the beaming of power to spacecraft leaving orbit has been considered.

Low power

A new company, Powercast introduced wireless power transfer technology using RF energy at the 2007 Consumer Electronics Show, winning best Emerging Technology.[13] The Powercast system is applicable for a number of devices with low power requirements. This could include LEDs, computer peripherals, wireless sensors, and medical implants. Currently, it achieves a maximum output of 6 volts for a little over one meter. It is expected for arrival late 2007.

High power

Wireless Power Transmission (using microwaves) is well proven. Experiments in the tens of kilowatts have been performed at Goldstone in California in 1975[15][16] and more recently (1997) at Gand Bassin on Reunion Island.

Dr. H

Answer 3

Yes, but where are you going to get these microwaves or radiowaves from? Those that reach us from the Sun are not intense enough to generate a usable amount.

Answer 4

Well, that would be a waste. You have to use electricity to make the waves and then you need convert them back to electricity. Because there's a loss in both processes, you'll be lucky to get back half the power you started with. If you're talking about the waves floating around because of radio stations etc, there's not enough energy to heat a teaspoon of water.

Answer 5

Yes you can, just connect any antenna to a bridge rectifier and charge a battery with it. But it's much more practical to use electromagnetic radiation from the sun with photovotaic cells.